


Reciprocity

by iqom_Archive (iqom)



Category: Undertale (Video Game)
Genre: AFAB reader - Freeform, Begging, Exhibitionism, F/M, Masturbation, Mettaton has both genetalia, Oral Sex, Plot What Plot/Porn Without Plot, Praise Kink, Shameless Smut, Teasing, dominant Mettaton
Language: English
Status: Completed
Published: 2018-07-08
Updated: 2018-07-08
Packaged: 2019-06-07 00:27:28
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,122
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15206795
Author URL: https://archiveofourown.org/users/iqom/pseuds/iqom_Archive
Summary: It's a rainy evening and you have a rather esteemed guest in your apartment. You know what you want. So does he.





	Reciprocity

**Author's Note:**

> Christ, I haven't written an x Reader in eons, so I apologize if I'm a bit rusty.  
> A rather self-serving piece, this one. ( ͡° ͜ʖ ͡°) Hope you enjoy it as much as I do.

“It’s a bit messy,” you remark apologetically, a bit embarrassed by the state of your shoebox apartment, “Sorry. I wasn’t expecting company tonight!”

“I hope I’m not intruding,” Mettaton murmurs, looking about the room. His eyes, pink with heart-shaped pupils, are wide with awe; it’s a rather run-of-the-mill —albeit small and cluttered— place you’ve got, but with the way he peers around at his surroundings one would think he were in some sort of grand museum.

“Oh! No, it’s not that,” you assure him as you close and lock the door behind you. “I just wish I could have cleaned up a bit for you, is all.”

“I like to see how humans live in their natural habitat,” he replies, running his fingers along the stucco walls as he ventures further into your place. You follow him, hands folded; his delicious perfume washes over you as he drifts ahead and for the millionth time that night you find yourself taken aback by his ethereal beauty. Tall and graceful, with broad shoulders and an impossibly tiny waist framed so delicately by his smart black suit jacket and form-fitting pencil skirt; he’s captivating, even from behind.

Your eyes travel downward.

Mm. _Especially_ from behind.

He makes his way across the studio space, stepping gingerly over your clothes strewn on the hardwood floor, to the window that looks over the city; the glittering lights look wet and wobbly in the torrential rainfall. He gazes out at the bustling city below as rain streaks the windowpane, running in rivulets down the glass. Thunder rumbles in the distance outside and you feel unbelievably relaxed... and confident.

“You have a lovely view,” he says softly as you come up behind him. Circling your arms around him, you lean up against his back, pressing your cheek between his shoulder blades.

You feel the synthetic muscles of his back ripple on your face as his head turns: a pair of soft, gloved hands grasp yours.

“Hi,” you whisper sweetly.

“Hello, darling,” he rumbles, rubbing small circles into your left hand with his thumb. Your heart hammers in your chest as you tighten your hold on him. In this particular pair of heels, you come up to his shoulder height, just tall enough to press your lips to the crook of his neck; you do so, sighing into the kiss, and he hums softly with gratitude. 

“You’re rather forward, aren’t you… I like that,” he murmurs as the sounds you make between kisses grow a bit more wet and lewd. It’s not like you could deny being desperate for him…

He turns in your arms, allowing you to press him up against the window as your lips meet. His are smooth and plastic, tasting of lipstick, and move deftly against yours with veteran expertise. You ease his suit jacket off wordlessly and he lets it fall to the floor.

His hands travel to your breasts; massaging them earnestly, flicking your hardened nipples with his thumbs through the cotton of your shirt. You whine as warmth pools between your legs at his touch; you thank him by cupping his face and kissing him along his square jaw.

“Sensitive here?” Mettaton purrs, having noticed your very obvious rise in excitement.

“V-Very,” you gasp as the pressure from his thumbs increases, squeezing and toying as he rubs out ripples of pleasure. You can feel yourself dampening between your legs so you lean into him and straddle his fluffy thigh, leisurely grinding on it, gasping as the wet fabric of your underwear feels deliciously cold against you.

His lips connect with yours again and you feel his plastic tongue flick between your teeth, probing curiously just inside your mouth. You meet him greedily with your own tongue, jousting while your hand creeps down his front, slipping beneath the waist of his skirt...

You’ve been wondering for a little while what Mettaton had to offer down there, but you figured that would be a bit of an inappropriate question to ask. You were perfectly happy with either, anyway…

Your hand finds hard, silky-smooth silicone at first; but as the robot groans happily, you continue searching and find rather unmistakeable soft, damp folds.

Wow. Both! How innovative! Mettaton whines shamelessly, his body quivering as you dip into his pussy before dragging your soaked fingertips up his length.

You push his skirt up past his hips and withdraw his cock from the confines of his panties, admiring its purple color and impossible smoothness in your palm as you stroke him. “God, Mettaton…” you whisper, leaning into him, “I can’t wait for you to fuck me…”

“Is that so?” he murmurs; his affected posh British accent (he’s a glamrock idol, through and through) is like music to your ears. “You don’t think… _mmm_... you have to earn that first?”

Your heart skips a beat as a violent shiver runs up your spine, and you decide right then and there that Mettaton displaying dominance is the hottest thing you’ve ever witnessed.

“H-how do I… do that?” you whisper, your mouth inches from his. He bites his lip, his face a portrait of mischief as he brings a hand up to your hair.

“I’m going to spread my legs on this windowsill,” he informs you in a voice like liquid chocolate, curling a lock of your hair around a long, skinny finger, “and you’re going to… service me. With your mouth.”

 _Fuck,_ your head is spinning; a gasp escapes your lips and you grasp the hand that’s by your face, planting feverish kisses on the gloved palm. He laughs lowly, clearly relishing in your enthusiasm, before sinking down to a seated position on the sill.

“On your knees, darling.”

You follow his instructions deliriously and relieve him of his underwear. Gripping the sill with his hands, he parts his high-heeled feet on the floor as promised, allowing you easy access.

You take a minute to admire everything between his legs and determine your course of action. His long, slender cock is situated directly above his pussy with only an inch or two of silicone skin separating them. “What should I… which one should I start with?” you breathe, awestruck.

He answers this question wordlessly; with one hand, he grasps his cock and moves it out of your way. With the other, he guides your head forward until your mouth is mere centimeters from the perfumed skin.

Your tongue flicks out, testing him, and Mettaton moans sharply. _Christ,_ what a heavenly sound...

Gripping his thighs, you press your lips to the soft flesh, kissing it lovingly like it were his mouth. You feel his hips roll against your face, his knuckles brushing your forehead as he slowly pumps his cock directly above.

“ _Ohhh… darling…”_

He groans as you re-introduce your tongue, lapping dutifully; his wetness tastes of cotton candy. Pressing a hand to the back of your skull, you feel him pushing you in deeper between his legs.

“Fuck, look at you…” he murmurs, his voice glitching with static as he strokes your hair. “Right where you belong.”

You moan into him and he spasms slightly, your warm breath undoubtedly giving him a shiver. Mettaton makes deliciously wet sounds as you tend to him, so you begin working in earnest now— tracing out the ABCs and creating zigzag patterns with your tongue. You’re dying to feel him unravel on your servile mouth, make the normally cool and composed robot wail shamefully as he cums for you…

You locate his clit blindly with your tongue and begin to gently suck; with a shattered gasp from above, his system re-lubricates without warning and your mouth and chin are covered in sticky sweetness. Holding you firmly in place, his hips rut disgracefully against your mouth as he fucks his other hand, his voice rising in pitch from sonorous to whiny as he grows increasingly more desperate.

“ _Yes darling, that’s it, oh my god, fuck, fuck, fuck--”_

You thrash your tongue between the silky folds, your face beginning to feel strained. The aching of your tongue only serves to encourage you, spurring you on; you squeeze his thighs as you work and the noise he makes is utterly obscene.

“Oh my _god,_ oh my _god, oh my god, I’m so close, I’m g-going to--”_

His words fall away to a howl of pleasure, his legs shaking as he finishes swiftly and violently in his hand. After a few moments, you pull away and draw your tongue up his quivering cock, savoring the delicious taste.

“Have I… earned it?” you ask saucily, drawing the back of your hand across your mouth and grinning widely at Mettaton. The android is completely undone before you, broad chest heaving, mouth ajar and eyelids fluttering.

“Oh, darling,” he murmurs, his voice high and breathy, “I’m going to fuck you until you can’t walk...”

 _Holy fuck!_ Something about that phrase lights a fire inside you and you gasp as you feel a sharp twinge between your legs. You rise unsteadily to your feet and your mouth collides with Mettaton’s, gripping his face feverishly, your movements only growing more eager and rough as you realize he’s certainly tasting himself on your lips.

He stands, hastily turning you until you're facing the window. “Hands on the glass,” he commands breathlessly as he reaches around you to fumble with the zipper of your jeans. You obey, and he drops your pants to your ankles, squeezing your asscheeks hard and pushing a sharp whine from your throat.

“You naughty thing,” he coos as he massages you, spreads you apart. The desperation burns between your legs, increasing thousandfold as he begins to slide your cotton panties down over the curve of your ass. You’re soaking wet by the time your panties reach the floor; with a violent shiver, you feel a bead of your cum dribble down your inner thigh.

“ _Please,_ Mettaton,” you groan, your voice hoarse, “I can barely stand it…”

“Mmmm…” You feel the end of his cock pressing against you, teasing little circles just outside your entrance, “You’re so adorable when you beg.”

His hands find purchase on your sides, holding you in place as he slips into you without so much as an iota of resistance. You release a strangled cry and he titters, clearly quite pleased with himself.

“ _God,_ I love humans,” he muses, his cock sliding out inch by languid inch before he snaps his hips forward in a brutal thrust, “So warm,” _thrust,_ “wet,” _thrust,_ “soft”, _thrust._ His cock feels unbelievable; its formidable length fills you spectacularly and your mind starts to go wild as you get caught up in the moment.

“ _Ahhh_ ,you’re so big,” you moan through gritted teeth, each thrust sending spats of ecstasy coursing through your body, “God, you feel so fucking good--”

Mettaton growls and picks up the pace considerably. Through the fog of pleasure you note that he seems to… _appreciate_ compliments, and your brain turns to that like a compass needle to a magnet.

“Oh, _god,_ you’re so perfect, you’re so _fucking perfect_ , fucking me in the _window!_ ” you exclaim as if you can’t really believe it’s happening yourself. It's unlikely that anyone can see you, given that your apartment is on the fourteenth floor; but you’ll be damned if it’s not hot. Mettaton seems to agree, squeezing your hips hard as he fucks you mercilessly. You can feel the pressure building within you, heightening even more as Mettaton leans forward onto your back, grasping desperately at your breasts as he presses his face into the crook of your neck.

“I’m going to ravage you,” he snarls directly in your ear, “You’re going to cum for me and you’re going to scream my name--”

You shudder in his arms, so dangerously close to your release. “Mettaton,” you manage as the feeling wells up like a sneaker wave, “Mettaton, _Mettaton, Mettaton--”_

He practically sobs in your ear, his thrusts jerky and erratic as he reaches his own peak.

“ _Mettaton, Mettat-ton, Mett-a-a-aah!”_

Your orgasm hits you like a train and you shriek helplessly, your back arching, muscles spasming, white spots obscuring your vision. As the feeling dissipates and Mettaton slides out of you, your legs quake and you lose your balance, nearly collapsing to the floor if not for Mettaton’s quick reflexes.

“W….wow…” you whisper, astonished, “You really keep your promises, don’t you?”

“Hmm?”

“I actually can’t walk now.”

He titters, drawing you up in his arms. “I must say, darling, rendering someone immobile has never felt so good.”

You lift a tired arm to push his tousled hair out of his face, once again in awe of his impossible beauty.

“Kiss me,” you request.

He obliges, holding you close, humming into your mouth.

**Author's Note:**

> iqomton.tumblr.com


End file.
